This invention relates to dental floss holders for facilitating the cleaning of teeth.
In the use of dental floss to clean one's own teeth it is often difficult to position and manipulate the floss for proper use. The floss must be stretched tightly, and the required force tends to cause the floss to slip off of or cut into the user's fingers. Also the user's hand is frequently too large to be comfortably inserted in his mouth sufficiently to place floss between the teeth farthest back in his mouth; in fact, the user ordinarily needs to use both hands to manipulate the dental floss anyway. In addition, when cleaning an entire set of teeth it usually becomes necessary to use several pieces of new dental floss as the floss becomes soiled. Thus even though the user may be able to find a comfortable way of holding one piece of dental floss that piece must be discarded and the user must find a comfortable way of holding a new piece of floss.
Mechanical dental floss holders have previously been designed for facilitating the cleaning of one's own teeth with a taut length of dental floss. For example, Kristmann U.S. Pat. No. 1,274,423 discloses a dental floss case which includes a chamber for holding a roll of dental floss and a forked end having a pair of prongs across which a length of dental floss is stretched. A principal drawback of the Kristmann device is that the shape of the forked end is not convenient for reaching all teeth within the user's mouth since the body of the device would have to be placed vertically adjacent the user's face in order to place the floss in gaps between the upper and lower front teeth. Another drawback is that the floss is threaded from inside the body of the device across the space between the aforementioned prongs, back inside the body of the device and out an opening near the source roll of dental floss. Consequently soiled floss will move through the body of the device as the floss is used up and may shed some of its waste material within the body of the device leading to unsanitary conditions which would tend to contaminate the unused floss and render the device unfit for placement within one's mouth without frequent cleaning. Also, since both the supply and free ends of the floss appear to be secured by the same locking mechanism it may be difficult to stretch the length of dental floss tightly between the two prongs of the forked end; in any case, the floss must be released by the time-consuming process unscrewing a knob.
Other dental floss holders, such as the devices disclosed in Casselman U.S. Pat. No. 3,746,017 and Henerlau U.S. Pat. No. 1,417,518, utilize tips having a gap facing to the side of holder handle, across which a length of dental floss is stretched. While dental floss holders having such tips may be more convenient for reaching some teeth than the forked end disclosed in the above-cited Kristmann device, they are unsatisfactory for reaching others.
Therefore it can be seen that there is a need for a dental floss holder which provides convenient access with a taut piece of floss to all teeth in the user's mouth and is capable of holding a sanitary supply of dental floss interior thereto for continuously replenishing the floss while minimizing contamination of the mouth from waste material previously collected on the floss. Furthermore the floss holder should be provided with a quickly-operated, easily-workable lock mechanism which grasps the fresh dental floss at its source for tightly stretching the dental floss when replacing soiled floss with new, clean material.